/*
 * Copyright 2019 Ververica GmbH
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.ververica.flinktraining.exercises.datastream_java.utils;

import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.table.api.Types;
import org.apache.flink.table.functions.ScalarFunction;

import java.sql.Timestamp;

public class TimeDiff extends ScalarFunction {

	public long eval(Timestamp first, Timestamp second) {
		return java.time.Duration.between(first.toInstant(), second.toInstant()).toMillis();
	}

	@Override
	public TypeInformation<?> getResultType(Class<?>[] signature) {
		return Types.LONG();
	}
}
